ARAP can connect to database servers in order to access, edit, and add data. The capability was developed for and tested with MySQL-type servers, but can in principal connect to many other servers (PostgreSQL, Microsoft, Oracle, etc.) - contact Nova Astronomics for advice if you need to do this.
Usually MySQL database servers run on Linux or Unix-type servers, however it is possible to install such a server on Windows too - the XAMPP software is a good choice.
The database configuration file "FDConnectionDefs.ini", located in the ARAP installation directory, needs to be created. It is in Windows "ini" configuration file format. See example:
The [aro] above is the name ARAP uses for the database. The next four parameters below need to indicate how to connect to the database. The file can contain one or more databases.
All database-related commands are accessed using the single ARAP command 'database' with one or more parameters added. All commands set the boolean variable DATABASEERROR to "true" if an error occurs or "false" if no error occurs.
Syntax: database command <option1> <option2> .. <option6>
Most database commands update the following variables:
- DATABASEERROR - "true" if a major database error occurred.
- "true" if: find command was not successful
- "true" if prior command is now at the first record
- "true" if next command is now at the last record
- "true" if first or last commands failed
- DATABASERECNO - the current table record pointer
- DATABASERECORDS - the number of records in the table (or filtered table)
Before using any other database commands, database open must be used.
The available database commands are below:
- open and close
- opentable and closetable
- getfield and setfield
- first and last
- prior and next
Syntax: database open databasename
This command connects to the database server and opens the database "databasename" as defined in the "FDConnectionDefs.ini" file. If this operation is successful, the variable DATABASECONNECTED is set to "true". All commands in this section must be preceded by this command.
Syntax: database close
This command terminates the connection with the currently open database and sets the variable DATABASECONNECTED to "false".
Syntax: database selecttable tableno
This command selects the active table number (1-10) to "tableno". This allows up to ten database tables to be open at the same time, each maintaining their own record pointer and filter parameter. Once set all other commands below operate on the selected table.
Syntax: database opentable tablename
This command opens the database table named "tablename".
Syntax: database closetable
This command closes the database table.
Syntax: database index field
This command sets which field or fields ("field") form the sort index. Some examples for "field" are below:
fieldname - sort on table field "fieldname" (default sort order)
fieldname:D - sort on table field "fieldname" descending
fieldname:A - sort on table field "fieldname" ascending
fieldname:DN - sort on table field "fieldname" descending (case-insensitive)
fieldname1;fieldname2 - sort on table field "fieldname1" then on "fieldname2"
Syntax: database find fieldname searchterm
This command searches for the first record where the field "fieldname" equals "searchterm". If found the record pointer is set to the record found. If not found, the variable DATABASESOFTERROR is "true".
Syntax: database filter <filterexpression>
This command filters the table using "filterexpression". Filtering a table causes records that don't match the filer expression to be disabled. This is an advanced feature - see this webpage for help on how "filterexpression" should be set.
Syntax: database getfield fieldname
This command sets the variable DATABASEFIELD to the value of the field "fieldname" at the current record.
Syntax: database setfield fieldname fieldvalue
This command sets field "fieldname" at the current record to "fieldvalue". It is not written to the database until the post command is executed.
Syntax: database getinfo
This command updates the variables DATABASERECNO and DATABASERECORDS.
Syntax: database setrecno recno
This command sets the record pointer to "recno".
Syntax: database delete
This command sets deletes the current record.
Syntax: database append
This command adds a new record and points to that record. The field values will be the default values.
Syntax: database refresh
This command refreshes the database - this handles the situation that can cause stale data if another program is writing to the database.
Syntax: database post
This command write all cached table data to the database.
Syntax: database first
This command sets the record pointer to the first record.
Syntax: database last
This command sets the record pointer to the last record.
Syntax: database prior
This command sets the record pointer to the next lower record number. It will not step past the first record.
Syntax: database next
This command sets the record pointer to the next higher record number. It will not step past the last record.